1. Field
Embodiments relate to an organic light-emitting device.
2. Description of the Related Art
Organic light-emitting devices (OLEDs), which are self-emitting devices, have advantages, e.g., a wide viewing angle, excellent contrast, quick response, high brightness, excellent driving voltage characteristics, and an ability to provide multicolored images.
A typical OLED has a structure including, e.g., a substrate, and an anode, a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and a cathode, which are sequentially stacked on the substrate. In this regard, the HTL, the EML, and the ETL may be organic thin films formed of organic compounds.
An operating principle of an OLED having the above-described structure is as follows.
When a voltage is applied to the anode and the cathode, holes injected from the anode move to the EML via the HTL, and electrons injected from the cathode move to the EML via the ETL. The holes and electrons recombine in the EML to generate excitons. When the excitons drop from an excited state to a ground state, light is emitted.